Certain hydrocarbon-bearing formations, especially those found at shallow depth, consist of semi- and unconsolidated sands that present problems during production. One such problem is movement of sand particles with produced fluids. This results in clogged bottomhole screens and reduced production, necessitating periodic cleaning of the well and screen or replacement of the latter. Present practice requires the use of work-over rig equipment, opening the well, insertion of tools operated from the surface and mechanically carrying out the cleaning operation.